Volume 15, No. 2, April 2015, Pages 517-528 PDF(498 KB)
Seasonal Variations and Sources of Carboxylic Acids in PM2.5 in Wuhan, China
Haotian Guo1, Jiabin Zhou1, Lei Wang1, Ying Zhou1, Jinpeng Yuan2, Rusong Zhao2
1 School of Resources and Environmental Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China
2 Key Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong Province, Analysis and Test Center, Shandong Academy of Sciences, Jinan 250014, China
- The first report on carboxylic acids in Wuhan, China.
- Provide insight into seasonal and spatial variations of carboxylic acids in Wuhan.
- Positive matrix factorization (PMF) was used to identify the source of carboxylic acids.
Aerosol PM2.5 samples collected from three sites in Wuhan, China, during 2011–2012 were analyzed by gas chromatography-mass spectrometry to better understand the molecular composition and sources of carboxylic acids. The concentrations of total monocarboxylic acids did not show apparent seasonal variations in Wuhan. Palmitic acid and stearic acid were the most abundant species, accounting for 32.4%–62.4% (average 51.8%) of all quantified monocarboxylic acids. Oxalic acid was found as the most dominant dicarboxylic acid, followed by succinic acid at the three sampling sites. The total concentration of dicarboxylic acids displayed obvious seasonal variation, with the highest in summer (1036.7–1546.4 ng/m3) and the lowest in winter (126.8–211.0 ng/m3). Positive matrix factorization (PMF) revealed that coal combustion, traffic-related emissions and biomass burning are the most important contributors to carboxylic acids at industrial site, downtown site and botanical garden, respectively. Plant waxes and secondary photochemical products are also significant sources of carboxylic acids at the three sampling sites.
Organic aerosols; Monocarboxylic acids; Dicarboxylic acids; Positive matrix factorization; Photochemical products.